Laxative abuse is not the way forward. I have been there myself. Do you really want to spend the rest of your life on the toilet, or thinking about when you'll next need to be on the toilet?
Regardless of what your weight is, your body deserves love and respect from you. If you struggle with overeating, try increasing your protein intake. I've recently started swapping my usual snacks for vegan protein bars and noticed my bowel habits are more regular. Protein bars not only satisfy you for longer than a normal cake/chocolate bar, but are also packed with fibre. I'm not suggesting to live off protein bars, but try substituting one of your snacks for a protein bar. Swap white bread/pasta/rice for brown wholemeal versions. Drink at least 2 litres of water each day. Your body will thank you for this.
The only thing laxatives will bring you long-term is a perforated bowel and regular rectum examinations at the hospital.